org.hobbit.utils

Class EnvVariables

java.lang.Object

org.hobbit.utils.EnvVariables

public class EnvVariables
extends Object

A simple class offering static access to environmental variables.

Author:

Michael Röder (michael.roeder@uni-paderborn.de)

Constructor Summary

Constructors

Constructor and Description
EnvVariables()

Method Summary

Modifier and Type	Method and Description
static boolean	getBoolean(String name) Returns the value of the environmental variable with the given name as boolean or throws an IllegalStateException if the variable can not be found or an error occurs.
static boolean	getBoolean(String name, boolean defaultValue) Returns the value of the environmental variable with the given name as boolean or the default value if the variable can not be found or an error occurs.
static boolean	getBoolean(String name, boolean defaultValue, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as boolean or the default value if the variable can not be found or an error occurs.
static boolean	getBoolean(String name, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as boolean or throws an IllegalStateException if the variable can not be found or an error occurs.
static boolean	getBoolean(String name, Supplier<Boolean> defaultValueFactory) Returns the value of the environmental variable with the given name as boolean or the default value if the variable can not be found or an error occurs.
static boolean	getBoolean(String name, Supplier<Boolean> defaultValueFactory, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as boolean or the default value if the variable can not be found or an error occurs.
protected static boolean	getBooleanValue(String name, boolean defaultValue, org.slf4j.Logger logger, boolean exceptionWhenFailing, boolean hasDefaultValue) Internal method defining the default value factory function before calling getBooleanValue(String, Supplier, Logger, boolean).
protected static boolean	getBooleanValue(String name, Supplier<Boolean> defaultValueFactory, org.slf4j.Logger logger, boolean exceptionWhenFailing) Internal method defining the conversion function before calling #getVariableValue(String, Function, Object, Logger).
static int	getInt(String name) Returns the value of the environmental variable with the given name as int or throws an IllegalStateException if the variable can not be found or an error occurs.
static int	getInt(String name, int defaultValue) Returns the value of the environmental variable with the given name as int or the default value if the variable can not be found or an error occurs.
static int	getInt(String name, int defaultValue, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as int or the default value if the variable can not be found or an error occurs.
static int	getInt(String name, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as int or throws an IllegalStateException if the variable can not be found or an error occurs.
static int	getInt(String name, Supplier<Integer> defaultValueFactory) Returns the value of the environmental variable with the given name as int or the default value if the variable can not be found or an error occurs.
static int	getInt(String name, Supplier<Integer> defaultValueFactory, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as int or the default value if the variable can not be found or an error occurs.
protected static int	getIntValue(String name, int defaultValue, org.slf4j.Logger logger, boolean exceptionWhenFailing, boolean hasDefaultValue) Internal method defining the default value factory function before calling getIntValue(String, Supplier, Logger, boolean).
protected static int	getIntValue(String name, Supplier<Integer> defaultValueFactory, org.slf4j.Logger logger, boolean exceptionWhenFailing) Internal method defining the conversion function before calling #getVariableValue(String, Function, Object, Logger).
static org.apache.jena.rdf.model.Model	getModel(String name) Returns the value of the environmental variable with the given name as Model or throws an IllegalStateException if the variable can not be found or an error occurs.
static org.apache.jena.rdf.model.Model	getModel(String name, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as Model or throws an IllegalStateException if the variable can not be found or an error occurs.
static org.apache.jena.rdf.model.Model	getModel(String name, org.apache.jena.rdf.model.Model defaultValue) Returns the value of the environmental variable with the given name as Model or the default value if the variable can not be found or an error occurs.
static org.apache.jena.rdf.model.Model	getModel(String name, org.apache.jena.rdf.model.Model defaultValue, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as Model or the default value if the variable can not be found or an error occurs.
static org.apache.jena.rdf.model.Model	getModel(String name, Supplier<org.apache.jena.rdf.model.Model> defaultValueFactory) Returns the value of the environmental variable with the given name as Model or the default value if the variable can not be found or an error occurs.
static org.apache.jena.rdf.model.Model	getModel(String name, Supplier<org.apache.jena.rdf.model.Model> defaultValueFactory, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as Model or the default value if the variable can not be found or an error occurs.
protected static org.apache.jena.rdf.model.Model	getModelValue(String name, org.apache.jena.rdf.model.Model defaultValue, org.slf4j.Logger logger, boolean exceptionWhenFailing, boolean hasDefaultValue) Internal method defining the default value factory function before calling getModelValue(String, Supplier, Logger, boolean).
protected static org.apache.jena.rdf.model.Model	getModelValue(String name, Supplier<org.apache.jena.rdf.model.Model> defaultValueFactory, org.slf4j.Logger logger, boolean exceptionWhenFailing) Internal method defining the conversion function before calling #getVariableValue(String, Function, Object, Logger).
static String	getString(String name) Returns the value of the environmental variable with the given name as String or throws an IllegalStateException if the variable can not be found or an error occurs.
static String	getString(String name, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as String or throws an IllegalStateException if the variable can not be found or an error occurs.
static String	getString(String name, String defaultValue) Returns the value of the environmental variable with the given name as String or the default value if the variable can not be found or an error occurs.
static String	getString(String name, String defaultValue, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as String or the default value if the variable can not be found or an error occurs.
static String	getString(String name, Supplier<String> defaultValueFactory) Returns the value of the environmental variable with the given name as String or the default value if the variable can not be found or an error occurs.
static String	getString(String name, Supplier<String> defaultValueFactory, org.slf4j.Logger logger) Returns the value of the environmental variable with the given name as String or the default value if the variable can not be found or an error occurs.
protected static String	getStringValue(String name, String defaultValue, org.slf4j.Logger logger, boolean exceptionWhenFailing, boolean hasDefaultValue) Internal method defining the default value factory function before calling getStringValue(String, Supplier, Logger, boolean).
protected static String	getStringValue(String name, Supplier<String> defaultValueFactory, org.slf4j.Logger logger, boolean exceptionWhenFailing) Internal method defining the conversion function before calling #getVariableValue(String, Function, Object, Logger).
protected static <T> T	getVariableValue(String name, Function<String,T> conversion, Supplier<T> defaultValueFactory, org.slf4j.Logger logger, boolean exceptionWhenFailing) Generic method for accessing an environmental variable which has the given name and will be transformed into the return type using the given conversion function.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

EnvVariables

public EnvVariables()

Method Detail

getVariableValue

protected static <T> T getVariableValue(String name,
                                        Function<String,T> conversion,
                                        Supplier<T> defaultValueFactory,
                                        org.slf4j.Logger logger,
                                        boolean exceptionWhenFailing)
                                 throws IllegalStateException

Generic method for accessing an environmental variable which has the given name and will be transformed into the return type using the given conversion function. The behavior in case of an error is defined by the given default value and Logger objects. If a problem occurs and a Logger is available, the error will be logged using the Logger.error(String) method. If exceptionWhenFailing is set to true an IllegalStateException is thrown. Else, if a defaultValueFactory is available, a default value will be returned. Otherwise null is returned.

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.

getString

public static String getString(String name)
                        throws IllegalStateException

Returns the value of the environmental variable with the given name as String or throws an IllegalStateException if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

Returns:

the variable value

Throws:

IllegalStateException - if the variable can not be found or an error occurs.

getString

public static String getString(String name,
                               String defaultValue)

Returns the value of the environmental variable with the given name as String or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getString

public static String getString(String name,
                               Supplier<String> defaultValueFactory)

Returns the value of the environmental variable with the given name as String or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getString

public static String getString(String name,
                               org.slf4j.Logger logger)
                        throws IllegalStateException

Returns the value of the environmental variable with the given name as String or throws an IllegalStateException if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value

Throws:

IllegalStateException - if the variable can not be found or an error occurs.

getString

public static String getString(String name,
                               String defaultValue,
                               org.slf4j.Logger logger)

Returns the value of the environmental variable with the given name as String or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getString

public static String getString(String name,
                               Supplier<String> defaultValueFactory,
                               org.slf4j.Logger logger)

Returns the value of the environmental variable with the given name as String or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getStringValue

protected static String getStringValue(String name,
                                       String defaultValue,
                                       org.slf4j.Logger logger,
                                       boolean exceptionWhenFailing,
                                       boolean hasDefaultValue)
                                throws IllegalStateException

Internal method defining the default value factory function before calling getStringValue(String, Supplier, Logger, boolean).

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

hasDefaultValue - flag indicating whether a default value has been provided.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.

getStringValue

protected static String getStringValue(String name,
                                       Supplier<String> defaultValueFactory,
                                       org.slf4j.Logger logger,
                                       boolean exceptionWhenFailing)
                                throws IllegalStateException

Internal method defining the conversion function before calling #getVariableValue(String, Function, Object, Logger).

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.

getModel

public static org.apache.jena.rdf.model.Model getModel(String name)
                                                throws IllegalStateException

Returns the value of the environmental variable with the given name as Model or throws an IllegalStateException if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

Returns:

the variable value

Throws:

IllegalStateException - if the variable can not be found or an error occurs.

getModel

public static org.apache.jena.rdf.model.Model getModel(String name,
                                                       org.apache.jena.rdf.model.Model defaultValue)

Returns the value of the environmental variable with the given name as Model or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getModel

public static org.apache.jena.rdf.model.Model getModel(String name,
                                                       Supplier<org.apache.jena.rdf.model.Model> defaultValueFactory)

Returns the value of the environmental variable with the given name as Model or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getModel

public static org.apache.jena.rdf.model.Model getModel(String name,
                                                       org.slf4j.Logger logger)
                                                throws IllegalStateException

Returns the value of the environmental variable with the given name as Model or throws an IllegalStateException if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value

Throws:

IllegalStateException - if the variable can not be found or an error occurs.

getModel

public static org.apache.jena.rdf.model.Model getModel(String name,
                                                       org.apache.jena.rdf.model.Model defaultValue,
                                                       org.slf4j.Logger logger)

Returns the value of the environmental variable with the given name as Model or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getModel

public static org.apache.jena.rdf.model.Model getModel(String name,
                                                       Supplier<org.apache.jena.rdf.model.Model> defaultValueFactory,
                                                       org.slf4j.Logger logger)

Returns the value of the environmental variable with the given name as Model or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getModelValue

protected static org.apache.jena.rdf.model.Model getModelValue(String name,
                                                               org.apache.jena.rdf.model.Model defaultValue,
                                                               org.slf4j.Logger logger,
                                                               boolean exceptionWhenFailing,
                                                               boolean hasDefaultValue)
                                                        throws IllegalStateException

Internal method defining the default value factory function before calling getModelValue(String, Supplier, Logger, boolean).

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

hasDefaultValue - flag indicating whether a default value has been provided.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.

getModelValue

protected static org.apache.jena.rdf.model.Model getModelValue(String name,
                                                               Supplier<org.apache.jena.rdf.model.Model> defaultValueFactory,
                                                               org.slf4j.Logger logger,
                                                               boolean exceptionWhenFailing)
                                                        throws IllegalStateException

Internal method defining the conversion function before calling #getVariableValue(String, Function, Object, Logger).

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.

getInt

public static int getInt(String name)
                  throws IllegalStateException

Returns the value of the environmental variable with the given name as int or throws an IllegalStateException if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

Returns:

the variable value

Throws:

IllegalStateException - if the variable can not be found or an error occurs.

getInt

public static int getInt(String name,
                         int defaultValue)

Returns the value of the environmental variable with the given name as int or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getInt

public static int getInt(String name,
                         Supplier<Integer> defaultValueFactory)

Returns the value of the environmental variable with the given name as int or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getInt

public static int getInt(String name,
                         org.slf4j.Logger logger)
                  throws IllegalStateException

Returns the value of the environmental variable with the given name as int or throws an IllegalStateException if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value

Throws:

IllegalStateException - if the variable can not be found or an error occurs.

getInt

public static int getInt(String name,
                         int defaultValue,
                         org.slf4j.Logger logger)

Returns the value of the environmental variable with the given name as int or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getInt

public static int getInt(String name,
                         Supplier<Integer> defaultValueFactory,
                         org.slf4j.Logger logger)

Returns the value of the environmental variable with the given name as int or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getIntValue

protected static int getIntValue(String name,
                                 int defaultValue,
                                 org.slf4j.Logger logger,
                                 boolean exceptionWhenFailing,
                                 boolean hasDefaultValue)
                          throws IllegalStateException

Internal method defining the default value factory function before calling getIntValue(String, Supplier, Logger, boolean).

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

hasDefaultValue - flag indicating whether a default value has been provided.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.

getIntValue

protected static int getIntValue(String name,
                                 Supplier<Integer> defaultValueFactory,
                                 org.slf4j.Logger logger,
                                 boolean exceptionWhenFailing)
                          throws IllegalStateException

Internal method defining the conversion function before calling #getVariableValue(String, Function, Object, Logger).

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.

getBoolean

public static boolean getBoolean(String name)
                          throws IllegalStateException

Returns the value of the environmental variable with the given name as boolean or throws an IllegalStateException if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

Returns:

the variable value

Throws:

IllegalStateException - if the variable can not be found or an error occurs.

getBoolean

public static boolean getBoolean(String name,
                                 boolean defaultValue)

Returns the value of the environmental variable with the given name as boolean or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getBoolean

public static boolean getBoolean(String name,
                                 Supplier<Boolean> defaultValueFactory)

Returns the value of the environmental variable with the given name as boolean or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getBoolean

public static boolean getBoolean(String name,
                                 org.slf4j.Logger logger)
                          throws IllegalStateException

Returns the value of the environmental variable with the given name as boolean or throws an IllegalStateException if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value

Throws:

IllegalStateException - if the variable can not be found or an error occurs.

getBoolean

public static boolean getBoolean(String name,
                                 boolean defaultValue,
                                 org.slf4j.Logger logger)

Returns the value of the environmental variable with the given name as boolean or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getBoolean

public static boolean getBoolean(String name,
                                 Supplier<Boolean> defaultValueFactory,
                                 org.slf4j.Logger logger)

Returns the value of the environmental variable with the given name as boolean or the default value if the variable can not be found or an error occurs.

Parameters:

name - name of the environmental variable which should be accessed

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

Returns:

the variable value or the default value if an error occurred and a default value is available.

getBooleanValue

protected static boolean getBooleanValue(String name,
                                         boolean defaultValue,
                                         org.slf4j.Logger logger,
                                         boolean exceptionWhenFailing,
                                         boolean hasDefaultValue)
                                  throws IllegalStateException

Internal method defining the default value factory function before calling getBooleanValue(String, Supplier, Logger, boolean).

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValue - the default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

hasDefaultValue - flag indicating whether a default value has been provided.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.

getBooleanValue

protected static boolean getBooleanValue(String name,
                                         Supplier<Boolean> defaultValueFactory,
                                         org.slf4j.Logger logger,
                                         boolean exceptionWhenFailing)
                                  throws IllegalStateException

Internal method defining the conversion function before calling #getVariableValue(String, Function, Object, Logger).

Parameters:

name - name of the environmental variable which should be accessed

conversion - the function which is used to convert the String of the variable value into the expected value type. It is assumed that this function will throw an exception if an error occurs.

defaultValueFactory - A factory method which can be used to generate a default value which will be returned if the variable can not be found or if an error occurs.

logger - the Logger which will be used to log errors if they occur.

exceptionWhenFailing - flag indicating whether an exception should be thrown if an error occurs.

Returns:

the variable value converted to the expected value or the default value if an error occurred and a default value is available.

Throws:

IllegalStateException - if exceptionWhenFailing is set to true and one of the following two errors occurs: 1) the variable is not available or 2) the conversion function throws an exception.